<template>
  <section class="real-app">
    <input type="text"
           class="add-input"
           autofocus="autofocus"
           placeholder="接下去要做什么？"
           @keyup.enter="addTodo">
    <item :todo="todo"
          v-for="todo in filteredTodos"
          :key="todo.id"
          @del="deleteTodo" />
    <tabs :filter="filter"
          :todos="todos"
          @toggle="toggleFilter"
          @clearAllCompleted="clearAllCompleted" />
  </section>
</template>

<script>
import Item from './item.vue'
import Tabs from './tabs.vue'
let id = 0
export default {
  data () {
    return {
      todos: [],
      filter: 'all'
    }
  },
  components: {
    Item,
    Tabs,
  },
  computed: {
    filteredTodos () {
      if (this.filter === 'all') {
        return this.todos
      }
      const completed = this.filter === 'completed'
      return this.todos.filter(todo => completed === todo.completed)
    }
  },
  methods: {
    addTodo (e) {
      this.todos.unshift({
        id: id++,
        content: e.target.value.trim(),
        completed: false
      })
      e.target.value = ''
    },
    deleteTodo (id) {
      this.todos.splice(this.todos.findIndex(todo => todo.id === id), 1)
    },
    toggleFilter (state) {
      this.filter = state
    },
    clearAllCompleted () {
      this.todos = this.todos.filter(todo => !todo.completed)
    }
  }
}
</script>

<style lang="stylus" scoped>
.real-app
  width: 600px
  margin: 0 auto
  box-shadow: 0 0 5px #666
.add-input
  position: relative
  margin: 0
  width: 100%
  font-size: 24px
  font-family: inherit
  font-weight: inherit
  line-height: 1.4em
  border: 0
  outline: none
  color: inherit
  padding: 6px
  border: 1px solid #999
  box-shadow: inset 0 -1px 5px 0 rgba(0, 0, 0, 0.2)
  box-sizing: border-box
  font-smoothing: antialiased
  padding: 16px 16px 16px 60px
  border: none
  box-shadow: inset 0 -2px 1px rgba(0, 0, 0, 0.03)
</style>


